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Abstract. Larval structural characters are an important component in phylogenetic reconstruction of the subfamily Paussinae. Based on larval characters, two main cladistic hypotheses have been proposed concerning basal relationships within Paussinae: (1) Metriini as sister-group of Ozaenini þ Paussini, with Ozaenini as a paraphyletic group and the genus Physea as sister-group of Paussini; and (2) Metriini as sister-group only of the monophyletic Ozaenini, with the Paussini as sister-group of Metriini þ Ozaenini. We present here a review of these hypotheses and a new cladistic analysis based on larvae, emphasizing the phylogeny of Ozaenini. The analysis includes the following taxa: Metrius (Metriini), Itamus, Pachyteles, Sphaerostylus, Physea (Ozaenini), Platyrhopalopsis and Paussus (Paussini). For both Physea and Platyropalopsis larvae we provide new detailed descriptions, because previous descriptions are inadequate to allow an advanced phylogenetic discussion. A total of fifty-six characters are analysed. Most characters show alternative states organized into sequences of character states, each of which is logically derivable from its neighbour in the sequence, resulting in an almost completely pectinate cladogram. Metrius is the sister-group of all other Paussinae, and Paussini are a highly derived offshoot within the ozaenine grade. According to the present analysis, Physea, regarded traditionally as a typical ozaenine, represents the ozeanine sister to Paussini, showing that Ozaenini are paraphyletic. As our analysis is based on the few paussine genera sufficiently known at the larval stage, which represent a low number of the extant paussine genera, the results are merely illustrative of the evolution of the major clades within the subfamily. More detailed information about the phylogeny of ozaenines could arise from a more comprehensive analysis, mainly including adult morphological characters.

Elevational gradients are characterized by strong abiotic variation within small geographical distances and provide a powerful tool to evaluate community response to variation in climatic and other environmental factors. We explored how temperature and habitat diversity shape the diversity of holometabolous predator and parasitoid insects along temperate elevational gradients in the European Alps. We surveyed insect communities along 12 elevational transects that were selected to separate effects of temperature from those of habitat diversity. Pitfall traps and pan traps were placed every 100 m of elevation increment along the transects ranging from 120 to 2200 m a.s.l. Sampling took place once a month from June to September 2015. Four groups characterized by having at least one life stage behaving as predator or parasitoid were examined: tachinids (Diptera), hoverflies (Diptera), sphecids (Hymenoptera) and ground beetles (Coleoptera). Species richness and evenness changed with elevation, but the shape and direction of the elevation-diversity patterns varied between groups. The effect of temperature on species richness was positive for all groups except for hoverflies. Habitat diversity did not affect species richness, while it modulated the evenness of most groups. Often, elevational patterns of species richness and evenness were contrasting. Our study indicates that natural enemies characterized by diverse ecological requirements can be differentially affected by temperature and habitat diversity across the same elevational gradients. As climate warming is predicted to increase mean annual temperatures and exacerbate weather variability, it is also expected to strongly influence natural enemies and their ability to regulate herbivore populations.